Snap-hook



J. A. LUTHI.

SNAP HOOK.

APPLICATION FILED AUG.I3, 1919.

1 ,352,982, Patented Sept. 14, 1920.

sr'res PATENT JosEF ALBERT m'irHLor LAcHEN-voNwIL, S ITZERLA D;

slur- 100K.

To all whom it may 00 ncern:

Be it known that I, Josnr a citizen of the Republic of Switzerland, residing at Lachen-Vonwil, Switzerland,' have invented certain new and useful Improvements in Snap-Hooks; and I do hereby declare the following to be a clear, full, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying draw ing, and to letters or figures of reference marked thereon, which form a part of this specification. V

This invention relates to improvements in snap-hooks. There are already known snap-hooks consisting of two members pivotally connected at their lower extremities. One of the members of such hoOks has abev eled face and an adjacent shoulder, whereby the two hook members are adaptedv to automatically interlock, one ofthe members being composed ofspring materials. The member composed of spring material of such hooks is however subjected temporarily or partially to the strain of the load, so that liable to break or to bend when subjected to sudden strains acting by jerks and in a lateraldirection, so that the desired safety in working can not be attained.

In order to provide a hook offering the required safety when used for harnessing horses, leashing animals or hoisting heavy loads, the hook accordlng to th1s invention comprises a guard member having the shape of a double armed lever adapted to act as a combined "hauling hook and a retaining spring engaging behind portions of the main body of the hook.

This'invention will now be more particularly described with reference to the accompanying drawing illustrating by way of example several modes of carrying out the invention. In this drawing:

Specification of Letters Patent. Patented/Sept, Application filed August 13. 1919. Serial No. 31 7309.

ALBERT Li'i'rrn,

at the free end of the arm 12 Figure 1 is a side view of a first embodiment, r

Fig. 2 is a cross-section on the line I I-II of Fig. 1; v i

Fig. 3 isa side view of a second embodiment and v Fig. 4 is a corresponding front view.

Fig. 5 is a side Vie of a third embodi- 1 ment, 7

Fig. 6 being the corresponding front view. Fig. 7 illustrates the different members of the hook shown in Figs. 5 and 6 in their closed or retaining position.

Referringat first to Figs. 1 and 2, a denotes the main body of the hook having curved ends forming retaining or supporting members 0Z and e and having, when seen in a s1de view, an S-shaped form. This I main body a is provided on its opposite lateral surfaces with two grooves f, g and shoulders it, i, through the middle of said body has, as

so that a cross-section v shown in'Fig. 2, also an S-shaped form.

Each of the curved ends a tively ofthe body a is fork-shaped, these ends being constituted by a tongue-like exrespectively and a tongue-like extension of the shoulders h and z'respectively. -Between V said extensions is provided on bothends-of the body a a double armed lever I) which forms an auxiliary retaining member or guard. Each of these levers is pivotally and 6 respectension of the bottom of the grooves f and 9 mounted on a bolt 0 and each of them co'm-.

prises a longer arm 6 and a shorter arm Z7 The shape of the latter is such that it rests in the closed or retaining position of the shaped portions of the ends 6 and d respectively. k denotes a bent portion provided of the levers b in order to facilitate a turning of the latter.

Let it be now assumed that the: described hook is suspended on an eye of a rope passing through the space inclosed by the memhers d and b when the latter are in th eir closed position, andthata second eye of the rope has to be seizedjby the curved end 6, this second eye reaching from beneath only up to the point as and not up to the supporting point 3 In such a case, the lever arm -b is forced through the eye of the rope and by turning this arm 6 the eye of the rope lever b wholly between the twotongueis then hauled until it rests on the point 2 Hereby the arm Z which is made of spring material is moved over the shoulder i and then snaps into the groove g, so. that the hook is also closed on its lower end.

\Vhen the lever arm Z9 is moved in the opposite direction to the arrow shown in Fi 1 out of the roove the smaller lever arm 6 forces the object that has beeir of the rope, out of the hook without raising the eye above the point Under all conditions the release of the eye from the members a? and 6 may be accomplished without-moving the rope longitudinally so that the rope and hook may be separated while under tension without exerting any addi tional strain or pull on the rope. Preferably the shorter arm 6 of the lever Z) is so shaped that its pointed end is not forced into the rope while the latter is forced out of the hook and does not engage-any threads of the latter. It is not absolutely necessary to give to the arm 6 a curved shape.

In the embodiment of the invention illustrated in Figs. 3 and 4:, the main body ahas the shape of a casing having a U-shaped cross-section. In this casing is pivotally mounted in the manner shown in Fig. a

the double armed lever 7). Then the hook is closed 2'. a. when the lever Z) assumes the position illustrated in Fig. 8 in point and dash lines, the longer arm 6 of the lever Z) rests wholly in the casing a in order to pre vent any displacement of said arm 6 when a lateral draft acts upon the hook, while the shorter, curved arm Z7 extends only with its pointed end 6 into the casing a. In this embodiment of the invention the shorter arm 6 of the lever b is adapted to haul any object, for instance the eye of a rope, from the point .r'to the point 9', while the longer arm 6 forces said object out of the hook when the latter is opened' A laterally projecting pin m on the arm F) engages into a recess n when the arm of the lever 72 is moved into the casing a, so that said arm I) is locked when it snaps into the casing. Instead of the recess 71 also a through-going hole may be provided on the casing a.

In the embodiment of the invention illustrat'ed in Figs. 5' to 7; a denotes again the main body of the hook forming a U-shaped casing and I) the double armed lever. The latter is provided near the free end of the arm 6 with a pi'ojecting portion 0 adapted to engage with a recess 29 provided in the on thiscasing so that any stretching of the curved ends e is prevented when the strain exerted by the object to be hoisted is very great. Above the recess p is provided at Q a lateral shoulder 8 adapted to act as a'stop forthe arm Z2 when the latter is moved.

into the casing In order that the arm 5 may snap in the proper manner behind said shoulder s, an oblique portion 2,- (F1ga 6') for instance is provided on thewall lying opposite the shoulder 5', said portion-t coirstricting the space inclosed between said two walls of the casing a. The shorter arm of the lever Z) is be'nt'in tl e embodiments of the invention shown to the-same 'extent 'as the curved end of the body'a.

In all of these forms'of construction it will be noted that the position of the pivot c is below the lowest point of" support' 1 of the retainin and su nortin' semi-hook D J. b

6 so that when a rope or chain is to be released the lever b is moved to releasing positlon WltllOUbplilClIlg additional tension on the rope or chain, as would be the case the pivot point 0 were above the point y. I'Vhat I claim now as my'invention is: 1. A snap hook comprising a casing sub stantially S-shaped incross section and having longitudinal grooves in the opposite sides hereof, a resilient double armed lever pivotally mounted. at each end 'of the casing, one arm of each of saidilevers constituting a hauling hook and the second arm of each lever adapted to engage in the grooves of the casing.

2. A snap'hook comprising a casing having grooves formeddn its opposite lateral a faces, a curved retaining inembenfornied on each end of the casing a spring metal .hook pivoted on each retaining member andhavinggan'arnradapted to extend over the casing and snap into thegroove tl'ierein.

3. A snap-hook comprising a body ortlon having a seIm-hook extension, a" hookshaped hauling lever ofsprii1g=metal whoselever arm is normally deflected: from its plane of movementysaid body portion hav ing a; lockingshoulderwithwhich said lever is arranged to snap into engagement.

In testimony'tliat I claim theforegoingas my invention, I have signed my name.

JOSEF ALBERT LITE-HQ; 

